/****
 * let   vs  const
 * 解构
 * 展开
 *  */
function f() {
    var message = "Hello World";
    var a = 10;
    return function g() {
        var b = a + 1;
        return b;
    };
}
var g = f();
g();
for (var i = 0; i < 10; i++) {
    (function (j) {
        setTimeout(function () { console.log(j); }, 100); //0---9
    })(i);
}
